Growing Citrus in the Northwest
Although you may not live in the subtropics, you can still enjoy the intoxicating flower fragrance and the sweet juicy favor from many of your favorite citrus trees and shrubs. Colorful edible fruits and dark glossy evergreen leaves make these plants a beautiful fresh addition to any home.
It may not be practical to grow large fruiting citrus trees outdoors in our climate, but it is possible to enhance a sunny area in your home or a summer patio with a containerized citrus plant. The fruits from the smaller citrus plant grown in a container are the same size as the fruits from a full grown citrus tree, and the flavors are just as delicious.
Location is important. Citrus will do best in full sun or at least 6 hours of sun a day.
Water as any container grown plant…let the plant get somewhat dry between watering, and water well until the water runs through the pot.
Fertilize with an acid fertilizer in the spring or summer prior to the flush of new growth and again in late August. There are fertilizers that are specifically designed for Citrus plants, like Espoma’s Citrus-Tone.
Pruning & Repotting - Dwarf citrus can grow to 6-8 feet, but can be pruned at any time to keep the plant compact and bushy. Repot in early spring (when you see signs of new growth) only if necessary (not yearly). They seem to like to be rootbound to encourage blooming. If you do not wish to pot up to a larger size, treat the plant as a bonsai; remove plant, trim some top growth and some root growth, add soil and replant in the same size container.
Pests – Look for common spider mites, mealy bug and scale. Use insecticidal soap, neem oil or horticultural oil. Look for honeydew as an indicator of insect problems. The best cure is prevention. Inspect your plant often to catch any problems early. Contact Al’s Indoor Plant Experts for further advice.
Temperatures - Citrus need cool temperatures in winter, but cannot tolerate temperatures much below freezing. Lots of light will promote blooming. During late fall, winter and early spring, keep under grow lights for 12 hours a day. They can lose their leaves in heat or whenever sudden changes in temperature, light levels or humidity occur. This is a normal reaction and the foliage will grow back as soon as the environment stabilizes.
In the spring, when nighttime temperatures consistently reach 50° F, it’s time to put your plant outside. Choose a site that gets morning sun with afternoon shade. As the plant acclimates to the sun, it can be gradually moved to a full sun position.
In fall, when the nighttime temperatures begin cooling below 50° F, bring your citrus indoors to a cool and bright location and enjoy the fragrance.
These citrus plants are hardy to Zone 9. In the Northwest, many folks who grow citrus keep them outdoors almost year-round. To protect against winter conditions – move containerized plants close to the house and out of winter wind and rain, remembering to water as needed. If the temperature drops below 30° F, bring the plant into a more protected area inside a garage where temperatures are above freezing. Return the plant outdoors when temperatures rise to 29° F or above.
Here are popular Citrus choices that have performed well in the Northwest:
Improved Meyer Lemon – Meyer Lemon is one of the most productive citrus trees, for its size. And best of all, it has thin-skinned fruits that are especially sweet and succulent.
Eureka Lemon – Produces an abundance of tart, juicy fruits with few seeds.
Bearss Lime – Vigorous and easily grown
with prolific white flowers followed by green-yellow fruit, these limes are medium-sized and relatively seedless.
Dwarf Washington Navel Orange – Delicious, easily peeled, seedless sweet fruit with a good orange flavor.
Kumquats – These are the ‘little gold gems’ of the citrus family. The kumquat has a thin, sweet peel and a zesty, somewhat tart center. The kumquat tastes best if it is gently rolled between the fingers before being eaten, as this releases the essential oils in the rind. Eat kumquats as you would eat grapes (with the peel). It is one of the hardiest of the citrus plants.